Geogrid is a major geosynthetic material, which has unique properties and efficacy compared with other geosynthetics. It is often used as a reinforcing material for reinforced soil structures or a reinforcing material for composite materials.
Geogrids are divided into four categories: plastic geogrids, steel-plastic geogrids, fiberglass geogrids, and polyester warp-knitted polyester geogrids. The grid is a two-dimensional grid or a three-dimensional grid screen with a certain height made of polypropylene, polyvinyl chloride, and other macromolecular polymers by thermoplastic or molding. When used as civil engineering, it is called a geogrid.
1 . Plastic Geogrid
The square or rectangular polymer mesh formed by stretching can be uniaxially stretched or biaxially stretched according to the different stretching directions during manufacture. It punches holes on the extruded polymer sheet (mostly polypropylene or high-density polyethylene) and then performs directional stretching under heating conditions. The uniaxially stretched grid is only made by stretching along the length direction of the sheet; the biaxially stretched grid is made by continuing to stretch the uniaxially stretched grid in the direction perpendicular to its length.
During the manufacture of the plastic geogrid, the macromolecules of the polymer will be rearranged and oriented during the heating and extension process, which strengthens the bonding force between the molecular chains and achieves the purpose of improving its strength. Its elongation is only 10% to 15% of the original sheet. If anti-aging materials such as carbon black are added to the geogrid, it can make it have better durability such as acid resistance, alkali resistance, corrosion resistance, and aging resistance.
2 . Mine geogrid
Mining geogrid is a kind of plastic mesh for underground coal mines. It is made of polypropylene as the main raw material. After being treated with flame retardant and antistatic technology, it is a “double-resistance” plastic mesh with an overall structure formed by biaxial stretching. The product is easy to construct, low cost, safe and beautiful
Mine geogrids are also known as two-way stretch plastic mesh false roofs in coal mines, referred to as false roof meshes. The mining geogrid is specially designed and manufactured for the false roof support and roadway support of the coal mine underground mining face. It is made of several high molecular polymers and filled with other modifiers. , Punching, stretching, shaping, coiling and other processes are manufactured. Compared with metal textile mesh and plastic woven mesh, mining geogrid has the characteristics of lightweight, high strength, isotropy, anti-static, non-corrosion, and flame retardant. It is a new type of coal mine underground support engineering and civil engineering. Use mesh geogrid material.
Mining geogrids are mainly used for false roof support projects in coal mine underground mining face, and mining geogrids can also be used for earth-rock anchoring and strengthening of other mine roadway engineering, slope protection engineering, underground civil engineering, and traffic road engineering. The material of mining geogrid is one of the best substitutes for plastic textile mesh.
Technical Advantages of Mining Geogrid:
- Friction is not easy to generate static electricity. In the underground environment of coal mines, the average surface resistance of plastic mesh is below 1×109Ω.
- Good flame retardant properties. It can reach the flame retardant properties specified by coal industry standards MT141-2005 and MT113-1995 respectively.
- Easy to clean coal. The density of the plastic mesh is about 0.92, which is less than the density of water. During the coal washing process, the broken mesh floats on the water surface and is easily washed away.
- Strong anti-corrosion ability and anti-aging.
- Easy to construct and transport. The plastic mesh is relatively soft, and it is not suitable for workers to be scratched during construction, and it has the advantages of easy curling and bundling, mining geogrid cutting and light weight, so it is convenient for underground transportation, carrying and construction.
- It has strong bearing capacity in both vertical and horizontal directions. Because this plastic mesh is biaxially stretched rather than woven, the mesh creep is small and the mesh size is uniform, which can effectively prevent the falling of broken coal and protect the safety of underground workers and the safety and security of mine workers. Safe operation of minecarts.
Application Fields of Mining Geogrid:
This product is mainly used for the support of coal mines in underground mining and can be used as supporting materials for various roadways such as bolt roadway, support roadway, bolt-and-shoot roadway, etc. When used for false roofs, it can be used in combination with two layers and above.
3. Steel Plastic Geogrid
The steel plastic geogrid is made of high-strength steel wire (or other fibers), specially treated, and polyethylene (PE), and other additives are added to make it a composite high-strength tensile strip through extrusion, and the surface has a rough pressure pattern, it is a high-strength reinforced geotextile belt. From this, the single belt is woven or sandwiched at a certain distance vertically and horizontally, and its junction is formed by welding its junction with a special strengthening bonding fusion welding technology, which is a reinforced geogrid.
Steel Plastic Geogrid Product Features:
- High strength and small deformation;
- Small creep;
- Corrosion resistance and long service life: The steel plastic geogrid is made of plastic material as a protective layer, supplemented by various additives to make it anti-aging and oxidation resistance, and can resist corrosion in harsh environments such as acid, alkali, and salt. Therefore, the steel plastic geogrid can meet the needs of various permanent projects for more than 100 years and has excellent performance and good dimensional stability.
- The construction is convenient and fast, the cycle is short, and the cost is low: the steel-plastic geogrid is easy to lay, overlap, locate, and level, avoiding overlapping and crossing, which can effectively shorten the project cycle and save 10%-50% of the project cost.
4. Fiberglass Geogrid
Fiberglass geogrid is made of glass fiber and a mesh structure material made by a certain weaving process. In order to protect the glass fiber and improve the overall performance, it is a geocomposite material made by a special coating process. The main components of glass fiber are silicon oxide, which is an inorganic material. Its physical and chemical properties are extremely stable, and it has high strength, high modulus, high wear resistance and excellent cold resistance, no long-term creep; thermal stability Good performance; the mesh structure makes the aggregate interlock and limit; improve the load-bearing capacity of the asphalt mixture. Because the surface is coated with special modified asphalt, it has dual composite properties, which greatly improves the wear resistance and shear capacity of the geogrid.
Sometimes combined with self-adhesive pressure-sensitive adhesive and surface asphalt impregnation treatment, the grille and the asphalt pavement are tightly integrated into one. As the interlocking force of earth and stone in the geogrid grid increases, the friction coefficient between them increases significantly (up to 08-10). The frictional bite force is stronger and significantly increased, so it is a good reinforcing material. At the same time, the geogrid is a kind of lightweight, flexible plastic flat mesh, which is easy to cut and connect on-site and can also be overlapped. The construction is simple and does not require special construction machinery and professional technicians.
Features of Fiberglass Geogrid
- High tensile strength, low elongation – glass fiber geogrid is made of glass fiber, which has high deformation resistance, and the elongation at break is less than 3%.
- No Long-Term Creep – As a reinforcing material, it is extremely important to have the ability to resist deformation under long-term load, i.e. creep resistance, glass fiber does not creep, which ensures that the product can maintain its performance for a long time.
- Thermal stability – the melting temperature of glass fiber is above 1000 ℃, which ensures the stability of glass fiber geogrid to withstand heat during paving operations.
- Compatibility with Asphalt Mixing – The material coated in the post-treatment process of the glass fiber geogrid is designed for the asphalt mixture, each fiber is fully coated and has high compatibility with asphalt, This ensures that the fiberglass geogrid will not be isolated from the asphalt mixture in the asphalt layer, but will be firmly combined.
- Physical and chemical stability – After being coated with special post-treatment agents, glass fiber geogrid can resist various physical wear and chemical erosion, as well as resist biological erosion and climate change, ensuring that its performance is not affected.
- Aggregate Interlocking and Confinement – Since the fiberglass geogrid is a mesh structure, the aggregate in the asphalt concrete can penetrate through it, thus forming a mechanical interlocking. This restriction impedes the movement of the aggregate, enabling the asphalt mixture to achieve better compaction, higher load-bearing capacity, better load transfer performance, and less deformation under load.
5. Polyester Fiber Warp Knitted Geogrid
Polyester fiber warp knitted geogrid uses high-strength polyester fiber as raw material. The warp knitting directional structure is adopted, and the warp and weft yarns in the fabric are not bent with each other. The intersections are bound and combined with high-strength fiber filaments to form a firm joint, giving full play to its mechanical properties. High-strength polyester fiber warp-knitted geogrid The grid has high tensile strength, small elongation force, large tear resistance strength, a small difference in vertical and horizontal strength, ultraviolet aging resistance, wear resistance, corrosion resistance, the lightweight, strong interlocking force with soil or gravel, and is suitable for reinforcing soil. Shear resistance and reinforcement improve the integrity and load capacity of the soil and play a significant role.
6. Biaxially Stretched Plastic Geogrid
It is suitable for all kinds of dam and roadbed reinforcement, slope protection, cave wall reinforcement, foundation reinforcement for permanent loads such as large airports, parking lots, docks, and freight yards.
Features of biaxially stretched plastic geogrid:
Increase the bearing capacity of the road (ground) foundation and prolong the service life of the road (ground) foundation.
Prevent the road (ground) from collapsing or cracking, and keep the ground beautiful and tidy.
The construction is convenient, time-saving, labor-saving, shortening the construction period and reducing maintenance costs.
Prevent culverts from cracking.
Reinforce soil slopes to prevent soil erosion.
Reduce the thickness of the cushion and save the cost.
Support the stable greening environment of the grass-planting mesh pad on the slope.
It can replace metal mesh and be used for false roof mesh in coal mines.
7. Uniaxially Stretched Geogrid
Uniaxially stretched geogrid is a kind of high molecular polymer as the main raw material, adding certain anti-ultraviolet and anti-aging additives. After uniaxial stretching, the originally scattered chain molecules are reoriented and arranged in a linear state. It is a high-strength geotechnical material that is extruded and pressed into a thin plate, punched into a regular mesh, and then stretched longitudinally. In this process, the macromolecules are brought into a directional linear state and an oblong network-like integral structure with uniform distribution and high node strength is formed. This kind of structure has quite high tensile strength and tensile modulus, and the tensile strength reaches 100-300KN/m, which is close to the level of low carbon steel, which is much better than traditional or existing reinforcement materials, especially the company Such products have high early-stage (2%-5% elongation) tensile strength and tensile modulus that exceed the international level. Provides the ideal force bearing and diffusion interlock system for the soil. The product has a high tensile strength (>150Mpa) and is suitable for various soils.
Uniaxially Stretched Geogrid Application
Used to strengthen weak foundations: Geogrids can rapidly increase the bearing capacity of foundations, control the development of settlement, and the confinement effect on the road base can effectively distribute the load to a wider subbase, thereby reducing the thickness of the base and reducing engineering costs. cost, shorten the construction period, and prolong the service life.
One-way geogrid is used for reinforced asphalt or cement pavement: geogrid is laid at the bottom of asphalt or cement pavement, which can reduce the depth of rutting, prolong the fatigue life of pavement, and reduce the thickness of asphalt or cement pavement to save costs.
It is used to reinforce the embankment, dam, and retaining wall: the filling of traditional embankments, especially high embankments, often require overfilling and the edge of the shoulder is not easy to be compacted, which leads to the later rainwater flooding of the slope and the phenomenon of collapse and instability. At the same time, it needs to use a relatively gentle slope, which covers a large area, and the retaining wall has the same problem. The use of geogrids to reinforce the embankment slope or retaining wall can reduce the floor space by half, prolong the service life, and reduce The cost is 20-50%.
Used to reinforce rivers and seawalls: It can be made into gabions, which can be used together with grilles to prevent the dams from being swept away by seawater and causing collapse. The gabions are permeable, which can slow down the impact of waves, prolong the life of the dams, save manpower and material resources, and shorten the construction period.
For landfill disposal: Geogrids are used in combination with other soil composite materials to treat landfills, which can effectively solve the problems of uneven foundation settlement and derived gas emissions, and can maximize the storage capacity of landfills.
Special use of one-way geogrid: low-temperature resistance. Adapt to -45℃—50℃ environment. It is suitable for the poor geology of less frozen soil, rich frozen soil, and high ice content frozen soil in the north.
It has high strength, small creep, and can adapt to various environmental soils, which can fully meet the use of tall retaining walls in high-grade highways.
It can effectively improve the interlocking and occlusal effect of the reinforced bearing surface, greatly enhance the bearing capacity of the foundation, effectively restrain the lateral displacement of the soil, and enhance the stability of the foundation.
Compared with the traditional grid, it has the characteristics of high strength, strong bearing capacity, corrosion resistance, anti-aging, large friction coefficient, uniform holes, convenient construction, and long service life.
It is more suitable for deep-sea operations and reinforcement of embankments, and fundamentally solves the technical problems of low strength, poor corrosion resistance, and short service life caused by long-term erosion of seawater for gabions made of other materials.
It can effectively avoid the construction damage caused by being crushed and damaged by the machine during the construction process
Geogrid Application Fields
It is suitable for roadbed reinforcement pavement reinforcement of various roads, railways, and airports.
It is suitable for foundation reinforcement of permanent loads such as large parking lots and dockyards.
It is suitable for slope protection of railways and highways.
Applicable culvert reinforcement.
It is suitable for the secondary reinforcement of the soil slope reinforced by the one-way tensile geogrid to further strengthen the soil slope and prevent soil erosion.
Mine, tunnel reinforcement.
Geogrid is suitable for various embankments and roadbed reinforcement, slope protection, and tunnel wall reinforcement. Large-scale airports, parking lots, dock freight yards, and other permanent bearing foundation reinforcement.
Geogrid is used to increase the bearing capacity of the road (ground) foundation and prolong the service life of the road (ground) foundation.
Geogrid is used to prevent the road (ground) from collapsing or cracking and keep the ground beautiful and tidy.
Geogrid is used for conventional construction, saving time and effort, shortening the construction period, and reducing maintenance costs.
Geogrids are used to prevent cracks in culverts.
Geogrids are used to enhance soil slopes and prevent soil erosion.
Geogrid is used to reduce the thickness of the cushion and save cost.
The geogrid is used to support the stable greening environment of the grass-planting mesh pad on the slope.
Geogrid can effectively block the transmission of seismic force and play an important role in enhancing the seismic stiffness, strength, and stability of the embankment.
The successful application of geogrid is expected to reduce various embankment diseases common in high-intensity earthquake areas and improve the earthquake resistance and disaster reduction ability of roads. However, the current seismic design codes for highways and railways have not made corresponding provisions on the seismic performance of geogrid-reinforced embankments.
At home and abroad, there are few studies on the seismic effect, reinforcement effect, and action mechanism of the geogrid-reinforced embankment.
The price of geogrid is mainly affected by the price of raw materials, whether it is a geogrid manufacturer, sea freight, and other factors. For the specific price, you can contact us for the latest quotation, and we can also provide you with free samples for your testing and experiments.
Geogrid Construction Technology
- First, accurately release the subgrade slope line. In order to ensure the width of the subgrade, each side is widened by 0.5m. After leveling the dried base soil, use a 12T vibratory roller, a tire roller above 25T or a 2.5T tamper to tamp the unevenness. Manual leveling (without thin-layer compensation and leveling).
- The medium (coarse) sand with a thickness of 0.3m is laid on the bed, and after manual leveling with the machine, the 25T vibratory roller is statically pressed twice.
- When laying geogrids, the bottom surface of the geogrids should be flat and dense. Generally, they should be flattened and straightened, and should not be curled or kinked. The two adjacent geogrids should be overlapped by 0.2m, and the geogrids should be aligned horizontally along the roadbed. The overlapping part of the grid is connected with No. 8 iron wire every 1m, and on the laid grid, it is fixed to the ground with U-shaped nails every 1.5-2m.
- After the first layer of geogrid is laid, start to fill the second layer of 0.2m thick medium (coarse) sand. The method is to transport the sand to the construction site and unload it on the side of the roadbed, and then push it forward with a bulldozer. After filling 0.1m within 2m on both sides of the roadbed, fold the first layer of geogrid up and fill it with 0.1m of medium (coarse) sand. It is forbidden to fill and advance from both sides to the middle. Work on the geogrid without filling medium (coarse) sand, so as to ensure that the geogrid is flat, without bulging or wrinkling. If the filling thickness is not uniform, use the 25T vibratory roller to statically press twice after the copying is correct.
- The construction method of the second layer of geogrid is the same as that of the first layer. Finally, 0.3m of medium (coarse) sand is filled. The filling method is the same as that of the first layer. After static pressing twice with a 25T road roller, the subgrade base is strengthened. It’s done.
- After the third layer (coarse) sand is rolled, two geogrids are laid on each side of the slope in the longitudinal direction of the line, overlapped by 0.16m, and connected by the same method, and then the earthwork construction is started, and the geogrids are laid. For slope protection, the laid side lines must be measured for each layer, and each side should ensure that the geogrid is buried within 0.10m of the slope after the slope is repaired.
- When the slope geogrid is filled with two layers of soil, that is, when the thickness is 0.8m, a layer of geogrid needs to be laid on both sides at the same time, and so on until it is laid under the surface soil of the road shoulder.
- After the subgrade is filled, the side slope shall be repaired in time, and the dry rubble protection shall be carried out at the foot of the slope. Except for the subgrade width of 0.3m on each side of this section, a settlement of 1.5% shall be reserved.